Which conflict was fought by the United States in the 1800s?

The Civil War was a pivotal conflict in American history that occurred between 1861 and 1865. It was fought primarily over issues such as states' rights and slavery, leading to a division between the Northern states (the Union) and the Southern states (the Confederacy). The war resulted in significant social, economic, and political changes in the United States, including the abolition of slavery.

In contrast, World War I, the Korean War, and the Vietnam War took place in the 20th century, with World War I occurring from 1914 to 1918, the Korean War from 1950 to 1953, and the Vietnam War spanning from the late 1950s to 1975. Each of these conflicts involved different geopolitical issues and concerns, further underscoring why the Civil War is the correct answer for conflicts occurring specifically in the 1800s. The Civil War’s ramifications are still felt today, making it a cornerstone of American history.